Lignin depolymerization and deoxygenation process for obtaining aromatic compounds and their catalytic reaction composition

Abstract

The present invention is related to a catalytic process, which includes catalytic compositions for depolymerisation and deoxygenation of lignin contained in the biomass for obtaining aromatic hydrocarbons. The catalytic composition includes at least one non-noble element from Group VIIIB of the periodic table supported on a mesoporous matrix composed of an inorganic oxide, which can be alumina surface-modified with a second inorganic oxide with the object of inhibiting the interaction between the active component and the support. The process of lignin depolymerisation includes dissolving lignin in a mixture of protic liquids, reacting it in a reaction system by batch or in continuous flow at inert and/or reducing atmosphere, at a temperature of between 60 to 320° C. and a pressure of from 5 to 90 kg/cm 2 .

The invention claimed is: 
     
       1. A catalytic composition for use in a process of lignin depolymerization and deoxygenation for obtaining aromatic hydrocarbons, comprising:
 a non-noble element of Group VIIIB of the periodic table, the non-noble element supported in a support material, wherein the support material comprises an inorganic oxide, the inorganic oxide selected from a mesoporous alumina modified by a second inorganic oxide, the second inorganic oxide selected from silicon dioxide to weaken the metal-support interaction, and wherein the material is mixed with a third silico aluminate component with a mesoporous zeolitic structure. 
 
     
     
       2. A process of lignin depolymerization and deoxygenation for obtaining aromatic hydrocarbons, comprising the steps of:
 dissolving a lignin in a mixture of protic solvents placed in a container, creating a dissolved protic lignin mixture, and sealing the container; 
 reacting the dissolved protic lignin mixture in one of a batch reaction system and a continuous flow reaction system at either an inert or reducing atmosphere; 
 stirring the dissolved protic lignin mixture; and 
 applying pressure with one of an inert gas and hydrogen pressure to the reaction system to maintain a set of determined reaction conditions for a determined reaction time; 
 wherein the reaction conditions include a determined reaction temperature of between 40° C. to 320° C., inclusive, and a determined operation pressure of from 5 kg/cm 2  to 100 kg/cm 2 , inclusive; and 
 the process is carried out using a catalytic composition according to  claim 1 . 
 
     
     
       3. The process of  claim 2 , wherein the support material has an area between 200 m 2 /g and 500 m 2 /g, inclusive, an average pore diameter from 8 nm to 30 nm, inclusive, and pore volume from 0.5 cc/g to 2.0 cc/g, inclusive. 
     
     
       4. The process of  claim 2 , wherein the composition further comprises a non-modified mesoporous alumina mixed with an aluminum oxyhydroxide in boehmite phase. 
     
     
       5. The catalytic composition of  claim 1 , wherein the non-noble element from Group VIIIB of the periodic table is selected from a group consisting of Fe, Co, and Ni. 
     
     
       6. The catalytic composition of  claim 1 , wherein the support material has an area between 200 m 2 /g and 500 m 2 /g, inclusive, an average pore diameter from 8 nm to 30 nm, inclusive, and pore volume from 0.5 cc/g to 2.0 cc/g, inclusive. 
     
     
       7. The catalytic composition of  claim 1 , further comprising a non-modified mesoporous alumina mixed with an aluminum oxyhydroxide in boehmite phase. 
     
     
       8. The process of  claim 2 , wherein the non-noble element from Group VIIIB of the periodic table is selected from a group consisting of Fe, Co, and Ni. 
     
     
       9. A catalytic composition for use in a process of lignin depolymerization and deoxygenation for obtaining aromatic hydrocarbons, comprising:
 a non-noble element of Group VIIIB of the periodic table, the non-noble element supported in a support material, wherein the support material comprises between 10% to 70%, inclusive, mesoporous alumina, 10% to 70%, inclusive, mesoporous zeolite, and 10% to 70%, inclusive, aluminum oxyhydroxide in boehmite phase. 
 
     
     
       10. The catalytic composition of  claim 9 , wherein the support material comprises between 30% to 70%, inclusive, mesoporous alumina and 30% to 70%, inclusive, aluminum oxyhydroxide in boehmite phase. 
     
     
       11. A process of lignin depolymerization and deoxygenation for obtaining aromatic hydrocarbons, comprising the steps of:
 dissolving a lignin in a mixture of protic solvents placed in a container, creating a dissolved protic lignin mixture, and sealing the container; 
 reacting the dissolved protic lignin mixture in one of a batch reaction system and a continuous flow reaction system at either an inert or reducing atmosphere; 
 stirring the dissolved protic lignin mixture; and 
 applying pressure with one of an inert gas and hydrogen pressure to the reaction system to maintain a set of determined reaction conditions for a determined reaction time; 
 wherein the reaction conditions include a determined reaction temperature of between 40° C. to 320° C., inclusive, and a determined operation pressure of from 5 kg/cm 2  to 100 kg/cm 2 , inclusive; and 
 the process is carried out using a catalytic composition according to  claim 9 . 
 
     
     
       12. The process of  claim 11 , wherein the support material comprises between 30% to 70%, inclusive, mesoporous alumina and 30% to 70%, inclusive, aluminum oxyhydroxide in boehmite phase.